Mr Gordon initially refused to answer the police's questions, saying that he wanted to give his testimony in front of a jury.
But on hearing that Ms Marten had told officers what had happened to the child, and then consulting with his lawyer, he started answering questions.
He said Ms Marten was suffering from a "post-traumatic thing"
He said the couple loved the baby and that it was "sad that it happened like that", adding:
"but I think… it's just one of those things.
Mark Gordon told detectives his partner was 'an excellent mother' who wanted to have the baby.
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